Improvement in sewing-machine shuttles



J. J. GRAFF.

SEWING-MACHINE SHUTTLE.

Patented June 6. 1876.

UNITED STATES PATENT OFFICEc JOSEPH J. GRAFF, OF SAN FRANCISCO, CAL.,ASSIGNOR OF ONE-HALF HIS RIGHT TO ORLA H. J'EWELL AND ANDREW SHOWERS, OFSAME PLACE.

IMPROVEMENT IN SEWING-MACHINE SHUTTLES.

Specification forming part of Letters Patent No. 178,43 l, dated J une6, 1876; application filed February 24, 1876.

To all whom it may concern:

Be it known that I, J osEPrI J. GRAFF, of San Francisco, State ofCalifornia, have invented an Improved 'Shuttle for Sewing-Ma chines, ofwhich the following is a specification:

My invention relates to an improvement in sewing-machine shuttles-tothat part known -as the tension or thread-controlling device; and itconsists in the combination or arrangelnent, with the shuttle, of apivoted plate or shield, that is provided with a spring within one side,so placed as to press against the side or upper part of the shuttle withmore or less force as the side of the plate is brought against theshuttle, the thread being drawn out between the spring and theshuttle-face, in the manner as will more fully appear hereinafter.

Figure l of the accompanying drawing shows a perspective view of ashuttle with the tension plate or shield opened. Fig. 2 is a top `viewof the face ofthe shuttle with the shield closed. Fig. 3 is a View ofthe shuttle, taken from the lower side of Fig. 2.

The shuttle B has the plate A pivoted to its face at the heel, so thatit will turn freely over the opening that contains the bobbin. The plateA has a shield, b, formed by bending down one side ot' the plate thatlies against the side ofthe shuttle, and upon the inside of this shieldis secured the tension-spring a. This spring is xed at one end to theside of the shield b, and is held in place by the pin o, projecting'from the shield, a slot in the end of the spring t allowing'. it to playas the pressure of the plate against the shuttle is changed. The twopins on the inner side of the shield b lit into holes in the face of.the shuttle, the pin o entering the hole l when the plate is closed.The end ot' the tension-plate A is made with a lip,f, that bears againstthe side of an eccentric button, C, upon the face of the shuttle nearthe point, so that as the eccentric is turned the shield b is pressedagainst the side of the shuttle with more or less force.

The bobbin thread passes out through a notch in the edge of the shuttle,(shown at e, Fig. 1,) and as it draws out from between the side of theshuttle and the spring a a friction or tension upon the thread isproduced.

From the foregoing description, and from an examination of Figs. l and 2of the drawing, it Will be seen that the pressure of the shield bagainst the side ot' the shuttle is increased as the eccentric C isturned in the direction ofthe arrow, Fig. 2, andthe thread rr, Fig. l,is caught between the face of the spring a and the side of the shuttle,and also that this tension is increased or diminished at Will.

The pins on the inner face of the shield or ledge b of the plate A keepthe thread from catching into the edge of the spring, or between theplate and the edge of the shuttle, as shown in Fig. l.

My invention, as thus. constructed, keeps the bobbin -thread frombecoming soiled, as the opening of the shuttle is covered and protectedby the plate, and an adjustable tension is provided, that is uniform inits action, whether the bobbin be full or nearly run out of thread, andthat is capable of being regu-l lated in a very delicate manner.

The construction of the shuttle is also rendered more simple and lessexpensive, as no tension-holes, slots, or bars are required.

Having thus fully described my invention, what I claim as new, .anddesire to secure by Letters Patent, is-

1. The combination, with a sewing-machine shuttle, of the pi votedtension plate A, with its ledge or shield Z1, having a tension-spring,ci, and the eccentric button C on the face of the shuttle, the wholearranged, combined, and operating as and for the purpose described andshown. v

2. The combination, with the tension-plate A, its ledge b, and spring a,of the projecting pins on the inner face of the ledge, that engage inholes in the side of the shuttle, in the manner and for the purposedescribed and shown.

In witness whereof I have hereunto set my hand and seal this 12th day ofFebruary, 1876.

J. J. GRAFF. [1.. s.]

Witnesses:

C. W. M. SMITH, PHILIP MAHLER.

